Radiological management of postoperative lymphorrhea

PURPOSE

Postoperative lymphorrhea can occur after different surgical procedures and may prolong the hospital stay due to the need for specific treatment. In this work, the therapeutic significance of the radiological management of postoperative lymphorrhea was assessed and illustrated.

METHOD

A standardized search of the literature was performed in PubMed applying the Medical Subject Headings (MeSH) term "lymphangiography." For the review, the inclusion criterion was "studies with original data on Lipiodol-based Conventional Lymphangiography (CL) with subsequent Percutaneous Lymphatic Intervention (PLI)." Different exclusion criteria were defined (e.g., studies with <15 patients). The collected data comprised of clinical background and indications, procedural aspects and types of PLI, and outcomes. In the form of a pictorial essay, each author illustrated a clinical case with CL and/or PLI.

RESULTS

Seven studies (corresponding to evidence level 4 [Oxford Centre for Evidence-Based Medicine]) accounting for 196 patients were included in the synthesis and analysis of data. Preceding surgery resulting in postoperative lymphorrhea included different surgical procedures such as extended oncologic surgery or vascular surgery. Central (e.g., chylothorax) and peripheral (e.g., lymphocele) types of postoperative lymphorrhea with a drainage volume of 100-4000 ml/day underwent CL with subsequent PLI. The intervals between "preceding surgery and CL" and between "CL and PLI" were 2-330 days and 0-5 days, respectively. CL was performed before PLI to visualize the lymphatic pathology (e.g., leakage point or inflow lymph ducts), applying fluoroscopy, radiography, and/or computed tomography (CT). In total, seven different types of PLI were identified: (1) thoracic duct (or thoracic inflow lymph duct) embolization, (2) thoracic duct (or thoracic inflow lymph duct) maceration, (3) leakage point direct embolization, (4) inflow lymph node interstitial embolization, (5) inflow lymph duct (other than thoracic) embolization, (6) inflow lymph duct (other than thoracic) maceration, and (7) transvenous retrograde lymph duct embolization. CL-associated and PLI-associated technical success rates were 97-100% and 89-100%, respectively. The clinical success rate of CL and PLI was 73-95%. CL-associated and PLI-associated major complication rates were 0-3% and 0-5%, respectively. The combined CL- and PLI-associated 30-day mortality rate was 0%, and the overall mortality rate was 3% (corresponding to six patients). In the pictorial essay, the spectrum of CL and/or PLI was illustrated.

CONCLUSION

The radiological management of postoperative lymphorrhea is feasible, safe, and effective. Standardized radiological treatments embedded in an interdisciplinary concept are a step towards improving outcomes.

Engineered ionizable lipid nanoparticles for targeted delivery of RNA therapeutics into different types of cells in the liver

Ionizable lipid nanoparticles (LNPs) have been widely used for in vivo delivery of RNA therapeutics into the liver. However, a main challenge remains to develop LNP formulations for selective delivery of RNA into certain types of liver cells, such as hepatocytes and liver sinusoidal endothelial cells (LSECs). Here, we report the engineered LNPs for the targeted delivery of RNA into hepatocytes and LSECs. The effects of particle size and polyethylene glycol-lipid content in the LNPs were evaluated for the hepatocyte-specific delivery of mRNA by ApoE-mediated cellular uptake through low-density lipoprotein receptors. Targeted delivery of RNA to LSECs was further investigated using active ligands. Incorporation of mannose allowed the selective delivery of RNA to LSECs, while minimizing the unwanted cellular uptake by hepatocytes. These results demonstrate that engineered LNPs have great potential for the cell type-specific delivery of RNA into the liver and other tissues.

Correlation of coronary microvascular function and diastolic dysfunction

Background

Coronary microvascular dysfunction (CMD) is an important mechanism for heart failure with preserved ejection fraction (HFpEF) which is closely related with diastolic dysfunction on transthoracic echocardiography (TTE).

Purpose

The aim of this study was to evaluate the association of CMD with echocardiographic parameters of diastolic dysfunction.

Methods

Total 385 patients with chest discomfort in the absence of significant coronary artery obstruction were enrolled to this study and underwent invasive coronary physiologic assessment including index of microcirculatory resistance (IMR), and coronary flow reserve (CFR). Echocardiographic parameters for diastolic dysfunction - left atrial volume index (LAVI) and left ventricular filling pressure (E over e') were compared in patients with true CMD (CFR&lt;2.5 with IMR ≥20), mismatched CMD (CFR≥2.5 with IMR ≥20 or CFR&lt;2.5 with IMR &lt;20), and no CMD (CFR≥2.5 with IMR &lt;20).

Results

Among the study population, 55 patients (14.3%) were true CMD, 162 patients (42.1%) were mismatched CMD and 168 patients (43.6%) were no CMD. Age (62.9±10.5 vs. 61.1±9.9 vs. 61.7±10.5, p=0.522) and left ventricular ejection fraction (63.9±8.1 vs. 63.9±6.2 vs. 63.0±6.7, p=0.414) was not different between groups. Patients with true CMD showed significantly larger left atrial size (LAVI: 34.7±18.2 mL/m2 vs. 26.8±10.7 mL/m2, p=0.005) and trend towards higher LV filling pressure (E/e': 10.8±3.5 vs. 9.9±3.5, p=0.073) compared with no CMD. In subgroup analysis, younger patients showed more pronounced increase of LAVI (Age &lt;65: 39.6±22.6 vs. 26.1±11.6, p=0.003; Age ≥65: 28.0±9.13 vs. 28.8±8.2, p=0.266; p for interaction 0.043) in true CMD compared to no CMD. Non-diabetic patients also showed more pronounced increase of E/e' in true CMD (Non-diabetes: 10.2±2.7 vs. 9.2±2.6, p=0.002; Diabetes: 12.1±4.5 vs. 11.9±5.1, p=0.197; p for interaction 0.015).

Conclusions

Coronary microvascular dysfunction is significantly related with echocardiographic parameters of diastolic dysfunction. The effect of CMD on diastolic dysfunction is more prominent in low-risk patients.

Figure 1

Funding Acknowledgement

Type of funding source: None

Abstract P2-06-01: Molecular characterization of human malignant phyllodes tumors reveals potential targeted approaches

Malignant phyllodes tumor (MPT) which belong to the fibroepithelial neoplasm spectrum is a rare type of breast malignancy, and currently there is no effective targeted approach available for MPT. In this study, we tried to identify key genomic alterations and biologic pathways in MPT by whole exome and RNA sequencing of nine MPT tissues. Whole exome sequencing revealed somatic alterations in EGFR, MED12, PIK3CA, PIK3R1, PDGFRA, PDGFRB, PTEN, and TP53. Transcriptome sequencing showed dysregulation of ECM-receptor interaction, focal adhesion, and PI3K-Akt signaling in MPTs when compared to normal breast or invasive breast cancer tissues. Based on the transcriptome profiles, the MPTs were classified into two subtypes; fibrous subtype with upregulation of stromal genes such as collagens and epithelial subtype with upregulation of E-cadherin and Claudins. The molecular classification of fibrous and epithelial subtypes was validated in 28 paraffin-embedded MPT tissues. The fibrous subtype showed higher mitotic index and increased risk for recurrence when compared to the epithelial subtype. We established a patient-derived xenograft model from one fibrous subtype MPT which harbored somatic mutation in PIK3R1 and PDGFRB. In that model, targeted treatment against PIK3CA/mTOR and PDGFR pathways effectively suppressed the tumor growth in vivo. Our data provide insights on the biologic understanding of MPT and suggest a clinically relevant molecular classification. Furthermore, we show that developing effective targeted approaches in MPT can be possible with genomic profiles and patient-derived xenograft models. The clinical efficacy of targeting PDGFR and PIK3CA/mTOR pathways in MPT should be tested in future clinical trials.

Citation Format: Moon H-G, Yun J, Hong BS, Lee E, Lee H-B, Han W, Kim J-I, Noh D-Y, Heo W, Hur S, Kang W, Lee C. Molecular characterization of human malignant phyllodes tumors reveals potential targeted approaches [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-06-01.

Endogenous Retroelements and the Host Innate Immune Sensors

The ability to distinguish between self and nonself is the fundamental basis of the immune system in all organisms. The conceptual distinction between self and nonself, however, breaks down when it comes to endogenous retroviruses and other retroelements. While some retroelements retain the virus-like features including the capacity to replicate and reinvade the host genome, most have become inactive through mutations or host epigenetic silencing. And yet, accumulating evidence suggests that endogenous retroelements, both active and inactive, play important roles not only in pathogenesis of immune disorders, but also in proper functioning of the immune system. This review discusses the recent development in our understanding of the interaction between retroelements and the host innate immune system. In particular, it focuses on the impact of retroelement transcripts on the viral RNA sensors such as Toll-like receptors, RIG-I-like receptors, protein kinase R, and the inflammasomes.

MR/GI/1 queues by positively correlated arrival stream

The effects of dependencies (such as association) in the arrival process to a single server queue on mean queue lengths and mean waiting times are studied. Markov renewal arrival processes with a particular transition matrix for the underlying Markov chain are used which allow us to change dependency properties without at the same time changing distributional conditions. It turns out that correlations do not seem to be pure effects, and three main factors are studied: (a) differences in the mean interarrival times in the underlying Markov renewal process, (b) intensity in the Markov renewal jump process, (c) variability in the point processes underlying the Markov renewal process. It is shown that the mean queue length can be made arbitrarily large in the class of queues with the same interarrival distributions and the same service time distributions (with fixed smaller than one traffic intensity), by making (a) large enough and (b) small enough. The existence of the moments of interest is confirmed and some stochastic comparison results for actual waiting times are shown.

Unusual cutaneous features associated with a heterozygous gain-of-function mutation in IFIH1: overlap between Aicardi-Goutières and Singleton-Merten syndromes

Cutaneous lesions described as chilblain lupus occur in the context of familial chilblain lupus or Aicardi-Goutières syndrome. To date, seven genes related to Aicardi-Goutières syndrome have been described. The most recently described encodes the cytosolic double-stranded RNA receptor IFIH1 (also known as MDA5), a key component of the antiviral type I interferon-mediated innate immune response. Enhanced type I interferon signalling secondary to gain-of-function mutations in IFIH1 can result in a range of neuroinflammatory phenotypes including classical Aicardi-Goutières syndrome. It is of note that none of the patients with a neurological phenotype so far described with mutations in this gene was reported to demonstrate cutaneous involvement. We present a family segregating a heterozygous pathogenic mutation in IFIH1 showing dermatological involvement as a prominent feature, variably associated with neurological disturbance and premature tooth loss. All three affected individuals exhibited increased expression of interferon-stimulated genes in whole blood, and the mutant protein resulted in enhanced interferon signalling in vitro, both in the basal state and following ligand stimulation. Our results further extend the phenotypic spectrum associated with mutations in IFIH1, indicating that the disease can be confined predominantly to the skin, while also highlighting phenotypic overlap with both Aicardi-Goutières syndrome and Singleton-Merten syndrome.

Homoisoflavanone prevents mast cell activation and allergic responses by inhibition of Syk signaling pathway

BACKGROUND

Mast cells play important roles in allergic inflammatory responses because they produce leukotrienes (LTs), prostaglandins (PGs), and a variety of inflammatory cytokines. Thus, pharmacological interventions for allergies have focused on inhibiting mast cell activation. Homoisoflavanone (HIF), isolated from Cremastra appendiculata Makino, has anti-angiogenic activities; however, its effects on allergic reactions have not been determined. The aim of this study was to assess the inhibitory effects of HIF on mast cell activation, which is critical for anti-allergic reaction and the underlying mechanisms.

METHODS

Enzyme-linked immunosorbent assays, quantitative real-time PCR, western blot analyses, and degranulation assay were performed to measure pro-inflammatory and allergic mediators in PMA/A23187- or IgE/antigen-stimulated mouse bone marrow-derived mast cells (BMMCs), HMC-1, RBL-1, or human PBMC-derived mast cells treated with or without HIF. The anti-allergic effects of HIF were determined in mouse models using dinitrophenol-immunoglobulin E-induced passive cutaneous anaphylaxis (PCA) and compound 48/80-induced ear swelling.

RESULTS

Homoisoflavanone down-regulated PGD2 , LTB4 , and LTC4 production and inhibited the production of pro-inflammatory cytokines, such as interleukin-6 and tumor necrosis factor-α in PMA/A23187- or IgE/antigen-stimulated mast cells. The molecular mechanisms by which HIF caused these inhibitory effects were determined to be the inactivation of spleen tyrosine kinase (Syk) signaling and the concurrent suppression of cPLA2 . HIF inhibited IgE-mediated PCA and compound 48/80-induced ear swelling in mouse.

CONCLUSIONS

Homoisoflavanone inhibited mast cell activation through the suppression of Syk pathway together with the inhibition of cPLA2 . Thus, it might be a good candidate molecule for allergic diseases.

Passive Wireless MEMS Microphones for Biomedical Applications

This paper introduces passive wireless telemetry based operation for high frequency acoustic sensors. The focus is on the development, fabrication, and evaluation of wireless, batteryless SAW-IDT MEMS microphones for biomedical applications. Due to the absence of batteries, the developed sensors are small and as a result of the batch manufacturing strategy are inexpensive which enables their utilization as disposable sensors. A pulse modulated surface acoustic wave interdigital transducer (SAW-IDT) based sensing strategy has been formulated. The sensing strategy relies on detecting the ac component of the acoustic pressure signal only and does not require calibration. The proposed sensing strategy has been successfully implemented on an in-house fabricated SAW-IDT sensor and a variable capacitor which mimics the impedance change of a capacitive microphone. Wireless telemetry distances of up to 5 centimeters have been achieved. A silicon MEMS microphone which will be used with the SAW-IDT device is being microfabricated and tested. The complete passive wireless sensor package will include the MEMS microphone wire-bonded on the SAW substrate and interrogated through an on-board antenna. This work on acoustic sensors breaks new ground by introducing high frequency (i.e., audio frequencies) sensor measurement utilizing SAW-IDT sensors. The developed sensors can be used for wireless monitoring of body sounds in a number of different applications, including monitoring breathing sounds in apnea patients, monitoring chest sounds after cardiac surgery, and for feedback sensing in compression (HFCC) vests used for respiratory ventilation. Another promising application is monitoring chest sounds in neonatal care units where the miniature sensors will minimize discomfort for the newborns.